1. Field of the Invention
This invention relates to a photo scanner device, and particularly, to an apparatus for changing the scanning range in a hologram photo scanner device.
2. Description of the Prior Art
An apparatus for scanning a laser beam by means of a polarizer is used for a laser printer, an image signal reader or the like. In consideration of various factors, including scanning speed, ease of manufacturing and the like, attention has been directed to a scanning optical system using a hologram disk in which a plurality of hologram grids are concentrically arranged on a rotary disk.
However, in such an optical scanner device, the scanning range is determined by the angle which each hologram forms with respect to a center of rotation thereof, and the size of the image cannot be changed.